1. Field of the Invention
The Present invention is directed to a novel class of 1,4-oxathiins bearing a substituted 3-amino group. More specifically, the present invention is directed to a novel class of substituted 1,4-oxathiins having a broader spectrum of fungicidal activity than known oxathiin fungicides.
2. Description of Related Art
The control of phytopathogenic fungi is of great economic importance since fungal growth on plants or on parts of plants, i.e., fruits, blossoms, foliage, stems, tubers, roots, inhibits production of foliage, fruit or seed and the overall quality of the harvested crop.
The 1,4-oxathiin 3-carboxanilides, for example, 5, 6-dihydro-2-methyl-1,4-oxathiin-3-carboxanilide, are well known for their excellent control of phytopathogenic fungi of the order basidiomycetes, (hereinafter B), but are much less effective against fungal organisms of the classes phycomycetes, ascomycetes and imperfecti (hereinafter P, A and I respectively). Examples of disclosures of 1,4-oxathiin-3-carboxanilide can be found in U.S. Pat. Nos. 3,249,499; 3,393,202; and 4,152,334.
The continuous economic toll, discussed above, taken by fungi establish a continuing need to develop new, more effective fungicides which possess curative, preventative and systemic action to protect cultivated plants. Those requirements must be accomplished without any adverse side effects, caused by the fungicide, on the plants to be protected.
Surprisingly, the compounds of the instant invention although prepared from oxathiin carboxanilide intermediates, have been found to have a different spectrum of activity allowing effective control of economically important phytopathogens of the classes phycomycetes, ascomycetes, and imperfecti.
Accordingly, this invention provides a new class of compounds which exhibit an unexpectedly desirable degree of fungicidal activity and methods of preparing same.
This invention also provides novel fungicidal compositions comprising such substituted 1,4-oxathiins.
Additionally, this invention provides a method for controlling fungi employing such fungicidal compositions.
The above objects and other additional objects will become more fully apparent from the following description and accompanying Examples.